001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *     https://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.configuration2.builder.combined;
018
019import org.apache.commons.configuration2.HierarchicalConfiguration;
020import org.apache.commons.configuration2.builder.BuilderParameters;
021import org.apache.commons.configuration2.builder.ConfigurationBuilder;
022import org.apache.commons.configuration2.builder.DefaultParametersHandler;
023import org.apache.commons.configuration2.builder.DefaultParametersManager;
024
025/**
026 * <p>
027 * Definition of a properties interface for the parameters of a combined configuration builder.
028 * </p>
029 * <p>
030 * This interface defines a number of properties for adapting the construction of a combined configuration based on a
031 * definition configuration. Properties can be set in a fluent style.
032 * </p>
033 * <p>
034 * <strong>Important note:</strong> This interface is not intended to be implemented by client code! It defines a set of
035 * available properties and may be extended even in minor releases.
036 * </p>
037 *
038 * @param <T> the return type of all methods for allowing method chaining
039 * @since 2.0
040 */
041public interface CombinedBuilderProperties<T> {
042
043    /**
044     * Registers a {@code DefaultParametersHandler} for child configuration sources. With this method an arbitrary number of
045     * handler objects can be set. When creating builders for child configuration sources their parameters are initialized
046     * by invoking all matching {@code DefaultParametersHandler}s on them. So, basically the same mechanism is used for the
047     * initialization of parameters for child configuration sources as for normal parameter objects.
048     *
049     * @param <D> the type of the handler to be registered
050     * @param paramClass the parameter class supported by the handler
051     * @param handler the {@code DefaultParametersHandler} to be registered
052     * @return a reference to this object for method chaining
053     * @see DefaultParametersManager#registerDefaultsHandler(Class, DefaultParametersHandler)
054     */
055    <D> T registerChildDefaultsHandler(Class<D> paramClass, DefaultParametersHandler<? super D> handler);
056
057    /**
058     * Registers a {@code DefaultParametersHandler} for child configuration sources derived from the given start class. This
059     * method works like the overloaded variant, but limits the application of the defaults handler to specific child
060     * configuration sources.
061     *
062     * @param <D> the type of the handler to be registered
063     * @param paramClass the parameter class supported by the handler
064     * @param handler the {@code DefaultParametersHandler} to be registered
065     * @param startClass an optional start class in the hierarchy of parameter objects for which this handler should be
066     *        applied
067     * @return a reference to this object for method chaining
068     * @see DefaultParametersManager#registerDefaultsHandler(Class, DefaultParametersHandler, Class)
069     */
070    <D> T registerChildDefaultsHandler(Class<D> paramClass, DefaultParametersHandler<? super D> handler, Class<?> startClass);
071
072    /**
073     * Registers the given {@code ConfigurationBuilderProvider} for the specified tag name. This means that whenever this
074     * tag is encountered in a configuration definition file, the corresponding builder provider is invoked.
075     *
076     * @param tagName the name of the tag (must not be <strong>null</strong>)
077     * @param provider the {@code ConfigurationBuilderProvider} (must not be <strong>null</strong>)
078     * @return a reference to this object for method chaining
079     * @throws IllegalArgumentException if a required parameter is missing
080     */
081    T registerProvider(String tagName, ConfigurationBuilderProvider provider);
082
083    /**
084     * Sets the base path for this combined configuration builder. Normally it it not necessary to set the base path
085     * explicitly. Per default, relative file names of configuration sources are resolved based on the location of the
086     * definition file. If this is not desired or if the definition configuration is loaded by a different means, the base
087     * path for relative file names can be specified using this method.
088     *
089     * @param path the base path for resolving relative file names
090     * @return a reference to this object for method chaining
091     */
092    T setBasePath(String path);
093
094    /**
095     * Sets a {@code DefaultParametersManager} object responsible for managing the default parameter handlers to be applied
096     * on child configuration sources. When creating builders for child configuration sources their parameters are
097     * initialized using this {@code DefaultParametersManager} instance. This way, meaningful defaults can be set. Note that
098     * calling this method overrides all {@code DefaultParametersHandler} objects previously set by one of the
099     * {@code registerChildDefaultsHandler()} methods! So either use this method if a pre-configured manager object is to be
100     * set or call the {@code registerChildDefaultHandler()} methods with the handlers to be registered (in the latter case,
101     * it is not necessary to set a {@code DefaultParametersManager} explicitly; a default one is created behind the
102     * scenes).
103     *
104     * @param manager the {@code DefaultParametersManager}
105     * @return a reference to this object for method chaining
106     */
107    T setChildDefaultParametersManager(DefaultParametersManager manager);
108
109    /**
110     * Sets the {@code ConfigurationBuilder} for the definition configuration. This is the configuration which contains the
111     * configuration sources that form the combined configuration.
112     *
113     * @param builder the definition {@code ConfigurationBuilder}
114     * @return a reference to this object for method chaining
115     */
116    T setDefinitionBuilder(ConfigurationBuilder<? extends HierarchicalConfiguration<?>> builder);
117
118    /**
119     * Sets the parameters object for the definition configuration builder. This property is evaluated only if the
120     * definition configuration builder is not set explicitly (using the {@link #setDefinitionBuilder(ConfigurationBuilder)}
121     * method). In this case, a builder for an XML configuration is created and configured with this parameters object.
122     *
123     * @param params the parameters object for the definition configuration builder
124     * @return a reference to this object for method chaining
125     */
126    T setDefinitionBuilderParameters(BuilderParameters params);
127
128    /**
129     * Sets a flag whether the child configurations created by a {@code CombinedConfigurationBuilder} should inherit the
130     * settings defined for the builder. This is typically useful because for configurations coming from homogeneous sources
131     * often similar conventions are used. Therefore, this flag is <strong>true</strong> per default.
132     *
133     * @param f the flag whether settings should be inherited by child configurations
134     * @return a reference to this object for method chaining
135     */
136    T setInheritSettings(boolean f);
137}